J/ApJ/964/12 ALMA-LEGUS. I. Molecular gas in NGC1313 and NGC7793 (Finn+, 2024)
ALMA-LEGUS.
I. The influence of galaxy morphology on molecular cloud properties.
Finn M.K., Johnson K.E., Indebetouw R., Costa A.H., Adamo A., Aloisi A.,
Bittle L., Calzetti D., Dale D.A., Dobbs C.L., Donovan Meyer J.,
Elmegreen B.G., Elmegreen D.M., Fumagalli M., Gallagher J.S., Grasha K.,
Grebel E.K., Kennicutt R.C., Krumholz M.R., Lee J.C., Messa M., Nair P.,
Sabbi E., Smith L.J., Thilker D.A., Whitmore B.C., Wofford A.
<Astrophys. J., 964, 12 (2024)>
=2024ApJ...964...12F 2024ApJ...964...12F
ADC_Keywords: Galaxies, nearby; Molecular clouds; Interstellar medium;
Millimetric/submm sources; Carbon monoxide; Optical;
Velocity dispersion
Keywords: Spiral galaxies ; Star formation ; Molecular clouds ;
Interstellar medium ; Young star clusters
Abstract:
We present a comparative study of the molecular gas in two galaxies
from the Legacy ExtraGalactic UV Survey (LEGUS) sample: barred spiral
NGC 1313 and flocculent spiral NGC 7793. These two galaxies have
similar masses, metallicities, and star formation rates, but NGC 1313
is forming significantly more massive star clusters than NGC 7793,
especially young massive clusters (<10Myr, >104M☉). Using
Atacama Large Millimeter/submillimeter Array (ALMA) CO(2-1)
observations of the two galaxies with the same sensitivity and
resolution (13pc), we directly compare the molecular gas in these two
similar galaxies to determine the physical conditions responsible for
their large disparity in cluster formation. By fitting size-line width
relations for the clouds in each galaxy, we find that NGC 1313 has a
higher intercept than NGC 7793, implying that its clouds have higher
kinetic energies at a given size scale. NGC 1313 also has more clouds
near virial equilibrium than NGC 7793, which may be connected to its
higher rate of massive cluster formation. However, these virially
bound clouds do not show a stronger correlation with young clusters
than with the general cloud population. We find surprisingly small
differences between the distributions of molecular cloud populations
in the two galaxies, though the largest of those differences is that
NGC 1313 has higher surface densities and lower freefall times.
Description:
NGC 1313 was observed by the Atacama Large Millimeter/submillimeter
Array (ALMA) in Band 6 (project code 2015.1.00782.S; PI: K.E. Johnson)
with the 12m array in Cycle 5 in 2018.
See Section 2.1 for further details.
NGC 7793 was observed by ALMA in Band 6 during Cycle 4 in 2016
(project code 2015.1.00782.S; PI: K. E. Johnson) with the 12m array.
See Section 2.2 for further details.
These two galaxies are included in the Legacy ExtraGalactic UV Survey
(LEGUS; Calzetti+ 2015AJ....149...51C 2015AJ....149...51C), a Hubble Space Telescope (HST)
Treasury Program that observed 50 nearby (<12Mpc) galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 126 588 Catalog of NGC 1313 dendrogram properties
table6.dat 126 531 Catalog of NGC 1313 clump properties
table7.dat 126 1078 Catalog of NGC 7793 dendrogram properties
table8.dat 126 965 Catalog of NGC 7793 clump properties
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See also:
J/AJ/128/16 : HIPASS Bright Galaxy Catalog (Koribalski+, 2004)
J/ApJ/686/948 : CO in extragalactic giant molecular clouds (Bolatto+, 2008)
J/ApJ/706/599 : Hα and UV SFR in the local volume (Lee+, 2009)
J/ApJS/197/16 : CO observations of LMC molecular clouds (MAGMA). (Wong+, 2011)
J/ApJ/772/107 : Giant molecular clouds in nearby gal. (Donovan Meyer+, 2013)
J/ApJ/784/3 : The PAWS catalogs of GMCs and islands in M51 (Colombo+, 2014)
J/ApJ/812/39 : Fluxes of NGG7793 & NGC4945 with GMOS-S (Stanghellini+, 2015)
J/ApJ/821/125 : SMA obs. of giant molecular clouds in NGC 300 (Faesi+, 2016)
J/ApJ/834/57 : MW molecular clouds from 12CO (Miville-Deschenes+, 2017)
J/ApJ/841/92 : Young massive star clusters in 2 LEGUS galaxies (Ryon+, 2017)
J/MNRAS/478/1611 : Local Volume H I Survey (LVHIS) (Koribalski+, 2018)
J/ApJS/235/23 : LEGUS galaxies1 observations (Sabbi+, 2018)
J/ApJ/860/172 : Cloud-scale molecular gas properties in 15 gal. (Sun+, 2018)
J/ApJS/245/14 : 8um cores in the spiral arms of nearby gal. (Elmegreen+, 2019)
J/ApJ/901/L8 : Molecular gas properties of 70 PHANGS-ALMA gal. (Sun+, 2020)
J/ApJS/257/43 : PHANGS-ALMA: arcsecond CO(2-1) imaging of gal. (Leroy+, 2021)
J/ApJ/909/121 : Young star clusters in NGC1313 with HST obs. (Messa+, 2021)
J/ApJ/927/149 : Low-J CO line ratios for 152 CO map pairs (Leroy+, 2022)
J/ApJ/932/47 : ALMA CO obs. of the 30 Dor MoC complex (Wong+, 2022)
J/MNRAS/520/63 : Cl* ages, masses & extinctions of 4 galaxies (Whitmore+, 2023)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID [1/676] Identification number
6- 13 F8.4 deg RAdeg [49.49/49.7] Right Ascension (J2000)
15- 22 F8.4 deg DEdeg [-66.52/-66.46] Declination (J2000)
24- 28 I5 K.km/s WCO [55/31470] Observed brightness of CO(2-1)
30- 31 I2 K.km/s e_WCO [2/31] Uncertainty in WCO
33- 36 F4.2 K COmax [1.1/8] Maximum CO(2-1) temperature
38- 42 F5.1 10+3Msun Mass [1.6/260] Mass
44- 48 F5.2 10+3Msun e_Mass [0.16/26] Uncertainty in Mass
50- 54 F5.2 pc Radius [0.14/10] Radius
56- 62 F7.5 pc e_Radius [8e-05/0.7] Uncertainty in Radius
64- 68 F5.1 km/s sigmav [3.6/85] Dispersion velocity
70- 74 F5.2 km/s e_sigmav [0.98/79] Uncertainty in sigmav
76- 82 F7.3 --- aVir [0.04/79] The virial parameter
84- 89 F6.3 --- e_aVir [0.03/41] Uncertainty in aVir
91- 95 F5.2 Msun/pc2 Sigma [1/92] Surface density
97- 103 F7.3 Msun/pc2 e_Sigma [0.12/540] Uncertainty in Sigma
105- 108 F4.2 [K/cm3] logPe/kB [0.47/5.5] Log external pressure divided
by kB
110- 114 F5.3 [K/cm3] e_logPe/kB [0.04/1.5] Uncertainty in logPe/kB
116- 120 F5.1 Myr tff [1.9/53] Free-fall time
122- 126 F5.2 Myr e_tff [0.66/46] Uncertainty in tff
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- ID [1/644] Identification number
6- 13 F8.4 deg RAdeg [49.49/49.7] Right Ascension (J2000)
15- 22 F8.4 deg DEdeg [-66.52/-66.46] Declination (J2000)
24- 28 I5 K.km/s WCO [47/7222] Observed brightness of CO(2-1)
30- 31 I2 K.km/s e_WCO [2/12] Uncertainty in WCO
33- 36 F4.2 K COmax [0.9/8] Maximum CO(2-1) temperature
38- 42 F5.1 10+3Msun Mass [1.3/61] Mass
44- 48 F5.2 10+3Msun e_Mass [0.14/6.1] Uncertainty in Mass
50- 54 F5.2 pc Radius [0.14/5.5] Radius
56- 62 F7.5 pc e_Radius [6e-05/0.4] Uncertainty in Radius
64- 68 F5.1 km/s sigmav [2.9/48] Dispersion velocity
70- 74 F5.2 km/s e_sigmav [0.98/21] Uncertainty in sigmav
76- 82 F7.3 --- aVir [0.043/48] The virial parameter
84- 89 F6.3 --- e_aVir [0.026/23] Uncertainty in aVir
91- 95 F5.2 Msun/pc2 Sigma [1/67] Surface density
97- 103 F7.3 Msun/pc2 e_Sigma [0.1/250] Uncertainty in Sigma
105- 108 F4.2 [K/cm3] logPe/kB [0.7/5.2] Log external pressure divided by
kB
110- 114 F5.3 [K/cm3] e_logPe/kB [0.04/1.4] Uncertainty in logPe/kB
116- 120 F5.1 Myr tff [2.1/54] Free-fall time
122- 126 F5.2 Myr e_tff [0.6/25] Uncertainty in tff
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Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- ID [1/1193] Identification number
6- 13 F8.4 deg RAdeg [359.4/359.5] Right Ascension (J2000)
15- 22 F8.4 deg DEdeg [-32.61/-32.56] Declination (J2000)
24- 28 I5 K.km/s WCO [52/54350] Observed brightness of CO(2-1)
30- 31 I2 K.km/s e_WCO [1/31] Uncertainty in WCO
33- 36 F4.2 K COmax [0.88/7] Maximum CO(2-1) temperature
38- 42 F5.1 10+3Msun Mass [1.3/390] Mass
44- 48 F5.2 10+3Msun e_Mass [0.13/39] Uncertainty in Mass
50- 54 F5.2 pc Radius [0.18/11] Radius
56- 62 F7.5 pc e_Radius [3e-05/0.7] Uncertainty in Radius
64- 68 F5.1 km/s sigmav [3.8/220] Dispersion velocity
70- 74 F5.2 km/s e_sigmav [0.9/98] Uncertainty in sigmav
76- 82 F7.3 --- aVir [0.12/120] The virial parameter
84- 89 F6.3 --- e_aVir [0.04/75] Uncertainty in aVir
91- 95 F5.2 Msun/pc2 Sigma [0.59/88] Surface density
97- 103 F7.3 Msun/pc2 e_Sigma [0.07/690] Uncertainty in Sigma
105- 108 F4.2 [K/cm3] logPe/kB [0.58/5.3] Log external pressure divided
by kB
110- 114 F5.3 [K/cm3] e_logPe/kB [0.2/7.6] Uncertainty in logPe/kB
116- 120 F5.1 Myr tff [2.2/120] Free-fall time
122- 126 F5.2 Myr e_tff [0.49/68] Uncertainty in tff
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Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- ID [1/1131] Identification number
6- 13 F8.4 deg RAdeg [359.4/359.5] Right Ascension (J2000)
15- 22 F8.4 deg DEdeg [-32.61/-32.56] Declination (J2000)
24- 28 I5 K.km/s WCO [38/15170] Observed brightness of CO(2-1)
30- 31 I2 K.km/s e_WCO [1/14] Uncertainty in WCO
33- 36 F4.2 K COmax [0.6/7] Maximum CO(2-1) temperature
38- 42 F5.1 10+3Msun Mass [1.1/110] Mass
44- 48 F5.2 10+3Msun e_Mass [0.1/11] Uncertainty in Mass
50- 54 F5.2 pc Radius [0.14/4.4] Radius
56- 62 F7.5 pc e_Radius [3e-05/0.3] Uncertainty in Radius
64- 68 F5.1 km/s sigmav [3.4/55] Dispersion velocity
70- 74 F5.2 km/s e_sigmav [0.9/30] Uncertainty in sigmav
76- 82 F7.3 --- aVir [0.1/59] The virial parameter
84- 89 F6.3 --- e_aVir [0.015/25] Uncertainty in aVir
91- 95 F5.2 Msun/pc2 Sigma [0.59/58] Surface density
97- 103 F7.3 Msun/pc2 e_Sigma [0.07/200] Uncertainty in Sigma
105- 108 F4.2 [K/cm3] logPe/kB [0.58/5.1] Log external pressure divided
by kB
110- 114 F5.3 [K/cm3] e_logPe/kB [0.043/1.4] Uncertainty in logPe/kB
116- 120 F5.1 Myr tff [2.6/68] Free-fall time
122- 126 F5.2 Myr e_tff [0.7/32] Uncertainty in tff
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History:
From electronic version of the journal
License: CC-BY-4.0
References:
Finn et al. Paper II. 2024ApJ...964...13F 2024ApJ...964...13F
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 27-May-2026